Support text-based expression sending and receiving on the server

cmd/inspect.go

@@ -68,7 +68,7 @@ func (cli *CLI) inspect(opts Options, dir string, filterFiles []string) int {
 			cli.formatter.Print(tflint.Issues{}, tflint.NewContextError("Failed to apply config to plugins", err), cli.loader.Sources())
 		}
 		for _, runner := range runners {
-			err = ruleset.Check(tfplugin.NewServer(runner))
+			err = ruleset.Check(tfplugin.NewServer(runner, cli.loader.Sources()))
 			if err != nil {
 				cli.formatter.Print(tflint.Issues{}, tflint.NewContextError("Failed to check ruleset", err), cli.loader.Sources())
 				return ExitCodeError

go.mod

@@ -19,6 +19,6 @@ require (
 	github.com/sourcegraph/go-lsp v0.0.0-20181119182933-0c7d621186c1
 	github.com/sourcegraph/jsonrpc2 v0.0.0-20190106185902-35a74f039c6a
 	github.com/spf13/afero v1.2.2
-	github.com/terraform-linters/tflint-plugin-sdk v0.1.1
+	github.com/terraform-linters/tflint-plugin-sdk v0.1.2-0.20200613135440-8f8f107dab08
 	github.com/zclconf/go-cty v1.4.2
 )

go.sum

@@ -221,7 +221,6 @@ github.com/hashicorp/golang-lru v0.5.1/go.mod h1:/m3WP610KZHVQ1SGc6re/UDhFvYD7pJ
 github.com/hashicorp/hcl v0.0.0-20170504190234-a4b07c25de5f h1:UdxlrJz4JOnY8W+DbLISwf2B8WXEolNRA8BGCwI9jws=
 github.com/hashicorp/hcl v0.0.0-20170504190234-a4b07c25de5f/go.mod h1:oZtUIOe8dh44I2q6ScRibXws4Ajl+d+nod3AaR9vL5w=
 github.com/hashicorp/hcl/v2 v2.0.0/go.mod h1:oVVDG71tEinNGYCxinCYadcmKU9bglqW9pV3txagJ90=
-github.com/hashicorp/hcl/v2 v2.3.0 h1:iRly8YaMwTBAKhn1Ybk7VSdzbnopghktCD031P8ggUE=
 github.com/hashicorp/hcl/v2 v2.3.0/go.mod h1:d+FwDBbOLvpAM3Z6J7gPj/VoAGkNe/gm352ZhjJ/Zv8=
 github.com/hashicorp/hcl/v2 v2.5.1 h1:5ytFZykUu2/4U59ogd2f+XZdi9+6oC/Tv5WzsH6fIDA=
 github.com/hashicorp/hcl/v2 v2.5.1/go.mod h1:bQTN5mpo+jewjJgh8jr0JUguIi7qPHUF6yIfAEN3jqY=
@@ -403,8 +402,8 @@ github.com/svanharmelen/jsonapi v0.0.0-20180618144545-0c0828c3f16d h1:Z4EH+5Effv
 github.com/svanharmelen/jsonapi v0.0.0-20180618144545-0c0828c3f16d/go.mod h1:BSTlc8jOjh0niykqEGVXOLXdi9o0r0kR8tCYiMvjFgw=
 github.com/tencentcloud/tencentcloud-sdk-go v3.0.82+incompatible/go.mod h1:0PfYow01SHPMhKY31xa+EFz2RStxIqj6JFAJS+IkCi4=
 github.com/tencentyun/cos-go-sdk-v5 v0.0.0-20190808065407-f07404cefc8c/go.mod h1:wk2XFUg6egk4tSDNZtXeKfe2G6690UVyt163PuUxBZk=
-github.com/terraform-linters/tflint-plugin-sdk v0.1.1 h1:5Y5FKoVWcmla//mkwz8E0k/bTcw86HMqDOMS8zDlGWY=
-github.com/terraform-linters/tflint-plugin-sdk v0.1.1/go.mod h1:MW/OviPYdTTq/aqzGkQW5vQ/zLF3F/LSrWTCTHFyt0o=
+github.com/terraform-linters/tflint-plugin-sdk v0.1.2-0.20200613135440-8f8f107dab08 h1:dUDhTQ3HFFIAV8/KecDj7z85BPlnN+FHf4fhhBk7l4U=
+github.com/terraform-linters/tflint-plugin-sdk v0.1.2-0.20200613135440-8f8f107dab08/go.mod h1:MW/OviPYdTTq/aqzGkQW5vQ/zLF3F/LSrWTCTHFyt0o=
 github.com/terraform-providers/terraform-provider-openstack v1.15.0 h1:adpjqej+F8BAX9dHmuPF47sUIkgifeqBu6p7iCsyj0Y=
 github.com/terraform-providers/terraform-provider-openstack v1.15.0/go.mod h1:2aQ6n/BtChAl1y2S60vebhyJyZXBsuAI5G4+lHrT1Ew=
 github.com/tmc/grpc-websocket-proxy v0.0.0-20171017195756-830351dc03c6/go.mod h1:ncp9v5uamzpCO7NfCPTXjqaC+bZgJeR0sMTm6dMHP7U=

langserver/handler.go

@@ -177,7 +177,7 @@ func (h *handler) inspect() (map[string][]lsp.Diagnostic, error) {
 			return ret, fmt.Errorf("Failed to apply config to plugins: %s", err)
 		}
 		for _, runner := range runners {
-			err = ruleset.Check(tfplugin.NewServer(runner))
+			err = ruleset.Check(tfplugin.NewServer(runner, loader.Sources()))
 			if err != nil {
 				return ret, fmt.Errorf("Failed to check ruleset: %s", err)
 			}

plugin/server.go

@@ -9,19 +9,26 @@ import (
 
 // Server is a RPC server for responding to requests from plugins
 type Server struct {
-	runner *tflint.Runner
+	runner  *tflint.Runner
+	sources map[string][]byte
 }
 
 // NewServer initializes a RPC server for plugins
-func NewServer(runner *tflint.Runner) *Server {
-	return &Server{runner: runner}
+func NewServer(runner *tflint.Runner, sources map[string][]byte) *Server {
+	return &Server{runner: runner, sources: sources}
 }
 
 // Attributes returns corresponding hcl.Attributes
 func (s *Server) Attributes(req *tfplugin.AttributesRequest, resp *tfplugin.AttributesResponse) error {
-	ret := []*hcl.Attribute{}
+	ret := []*tfplugin.Attribute{}
 	err := s.runner.WalkResourceAttributes(req.Resource, req.AttributeName, func(attr *hcl.Attribute) error {
-		ret = append(ret, attr)
+		ret = append(ret, &tfplugin.Attribute{
+			Name:      attr.Name,
+			Expr:      attr.Expr.Range().SliceBytes(s.sources[attr.Expr.Range().Filename]),
+			ExprRange: attr.Expr.Range(),
+			Range:     attr.Range,
+			NameRange: attr.NameRange,
+		})
 		return nil
 	})
 	*resp = tfplugin.AttributesResponse{Attributes: ret, Err: err}
@@ -30,7 +37,12 @@ func (s *Server) Attributes(req *tfplugin.AttributesRequest, resp *tfplugin.Attr
 
 // EvalExpr returns a value of the evaluated expression
 func (s *Server) EvalExpr(req *tfplugin.EvalExprRequest, resp *tfplugin.EvalExprResponse) error {
-	val, err := s.runner.EvalExpr(req.Expr, req.Ret, cty.Type{})
+	expr, diags := tflint.ParseExpression(req.Expr, req.ExprRange.Filename, req.ExprRange.Start)
+	if diags.HasErrors() {
+		return diags
+	}
+
+	val, err := s.runner.EvalExpr(expr, req.Ret, cty.Type{})
 	if err != nil {
 		if appErr, ok := err.(*tflint.Error); ok {
 			err = tfplugin.Error(*appErr)
@@ -42,7 +54,12 @@ func (s *Server) EvalExpr(req *tfplugin.EvalExprRequest, resp *tfplugin.EvalExpr
 
 // EmitIssue reflects a issue to the Runner
 func (s *Server) EmitIssue(req *tfplugin.EmitIssueRequest, resp *interface{}) error {
-	s.runner.WithExpressionContext(req.Meta.Expr, func() error {
+	expr, diags := tflint.ParseExpression(req.Expr, req.ExprRange.Filename, req.ExprRange.Start)
+	if diags.HasErrors() {
+		return diags
+	}
+
+	s.runner.WithExpressionContext(expr, func() error {
 		s.runner.EmitIssue(req.Rule, req.Message, req.Location)
 		return nil
 	})

plugin/server_test.go

@@ -6,7 +6,6 @@ import (
 	"github.com/google/go-cmp/cmp"
 	"github.com/google/go-cmp/cmp/cmpopts"
 	hcl "github.com/hashicorp/hcl/v2"
-	"github.com/hashicorp/hcl/v2/hclsyntax"
 	tfplugin "github.com/terraform-linters/tflint-plugin-sdk/tflint"
 	"github.com/terraform-linters/tflint/tflint"
 	"github.com/zclconf/go-cty/cty"
@@ -18,7 +17,7 @@ resource "aws_instance" "foo" {
   instance_type = "t2.micro"
 }`
 
-	server := NewServer(tflint.TestRunner(t, map[string]string{"main.tf": source}))
+	server := NewServer(tflint.TestRunner(t, map[string]string{"main.tf": source}), map[string][]byte{"main.tf": []byte(source)})
 	req := &tfplugin.AttributesRequest{
 		Resource:      "aws_instance",
 		AttributeName: "instance_type",
@@ -33,25 +32,14 @@ resource "aws_instance" "foo" {
 	if resp.Err != nil {
 		t.Fatalf("The response has an unexpected error: %s", resp.Err)
 	}
-	expected := []*hcl.Attribute{
+	expected := []*tfplugin.Attribute{
 		{
 			Name: "instance_type",
-			Expr: &hclsyntax.TemplateExpr{
-				Parts: []hclsyntax.Expression{
-					&hclsyntax.LiteralValueExpr{
-						Val: cty.StringVal("t2.micro"),
-						SrcRange: hcl.Range{
-							Filename: "main.tf",
-							Start:    hcl.Pos{Line: 3, Column: 20},
-							End:      hcl.Pos{Line: 3, Column: 28},
-						},
-					},
-				},
-				SrcRange: hcl.Range{
-					Filename: "main.tf",
-					Start:    hcl.Pos{Line: 3, Column: 19},
-					End:      hcl.Pos{Line: 3, Column: 29},
-				},
+			Expr: []byte(`"t2.micro"`),
+			ExprRange: hcl.Range{
+				Filename: "main.tf",
+				Start:    hcl.Pos{Line: 3, Column: 19},
+				End:      hcl.Pos{Line: 3, Column: 29},
 			},
 			Range: hcl.Range{
 				Filename: "main.tf",
@@ -65,12 +53,9 @@ resource "aws_instance" "foo" {
 			},
 		},
 	}
-	opts := []cmp.Option{
-		cmpopts.IgnoreUnexported(cty.Type{}, cty.Value{}),
-		cmpopts.IgnoreFields(hcl.Pos{}, "Byte"),
-	}
-	if !cmp.Equal(expected, resp.Attributes, opts...) {
-		t.Fatalf("Attributes are not matched: %s", cmp.Diff(expected, resp.Attributes, opts...))
+	opt := cmpopts.IgnoreFields(hcl.Pos{}, "Byte")
+	if !cmp.Equal(expected, resp.Attributes, opt) {
+		t.Fatalf("Attributes are not matched: %s", cmp.Diff(expected, resp.Attributes, opt))
 	}
 }
 
@@ -80,13 +65,13 @@ variable "instance_type" {
   default = "t2.micro"
 }`
 
-	server := NewServer(tflint.TestRunner(t, map[string]string{"main.tf": source}))
+	server := NewServer(tflint.TestRunner(t, map[string]string{"main.tf": source}), map[string][]byte{"main.tf": []byte(source)})
 	req := &tfplugin.EvalExprRequest{
-		Expr: &hclsyntax.ScopeTraversalExpr{
-			Traversal: hcl.Traversal{
-				hcl.TraverseRoot{Name: "var"},
-				hcl.TraverseAttr{Name: "instance_type"},
-			},
+		Expr: []byte(`var.instance_type`),
+		ExprRange: hcl.Range{
+			Filename: "template.tf",
+			Start:    hcl.Pos{Line: 1, Column: 1},
+			End:      hcl.Pos{Line: 1, Column: 1},
 		},
 		Ret: "", // string value
 	}
@@ -113,13 +98,13 @@ variable "instance_type" {
 func Test_EvalExpr_errors(t *testing.T) {
 	source := `variable "instance_type" {}`
 
-	server := NewServer(tflint.TestRunner(t, map[string]string{"main.tf": source}))
+	server := NewServer(tflint.TestRunner(t, map[string]string{"main.tf": source}), map[string][]byte{"main.tf": []byte(source)})
 	req := &tfplugin.EvalExprRequest{
-		Expr: &hclsyntax.ScopeTraversalExpr{
-			Traversal: hcl.Traversal{
-				hcl.TraverseRoot{Name: "var"},
-				hcl.TraverseAttr{Name: "instance_type"},
-			},
+		Expr: []byte(`var.instance_type`),
+		ExprRange: hcl.Range{
+			Filename: "template.tf",
+			Start:    hcl.Pos{Line: 1, Column: 1},
+			End:      hcl.Pos{Line: 1, Column: 1},
 		},
 		Ret: "", // string value
 	}
@@ -133,7 +118,7 @@ func Test_EvalExpr_errors(t *testing.T) {
 	expected := tfplugin.Error{
 		Code:    tfplugin.UnknownValueError,
 		Level:   tfplugin.WarningLevel,
-		Message: "Unknown value found in :0; Please use environment variables or tfvars to set the value",
+		Message: "Unknown value found in template.tf:1; Please use environment variables or tfvars to set the value",
 		Cause:   nil,
 	}
 	if !cmp.Equal(expected, resp.Err) {
@@ -150,7 +135,7 @@ func Test_EmitIssue(t *testing.T) {
 		},
 	}
 
-	server := NewServer(runner)
+	server := NewServer(runner, map[string][]byte{})
 	req := &tfplugin.EmitIssueRequest{
 		Rule:    rule,
 		Message: "This is test rule",
@@ -159,6 +144,12 @@ func Test_EmitIssue(t *testing.T) {
 			Start:    hcl.Pos{Line: 3, Column: 3},
 			End:      hcl.Pos{Line: 3, Column: 30},
 		},
+		Expr: []byte("1"),
+		ExprRange: hcl.Range{
+			Filename: "template.tf",
+			Start:    hcl.Pos{Line: 1, Column: 1},
+			End:      hcl.Pos{Line: 1, Column: 1},
+		},
 	}
 	var resp interface{}
 

tflint/terraform.go

@@ -9,6 +9,8 @@ import (
 	"path/filepath"
 	"strings"
 
+	hcl "github.com/hashicorp/hcl/v2"
+	"github.com/hashicorp/hcl/v2/hclsyntax"
 	"github.com/hashicorp/terraform/configs"
 	"github.com/hashicorp/terraform/terraform"
 	"github.com/zclconf/go-cty/cty"
@@ -49,6 +51,25 @@ func ParseTFVariables(vars []string, declVars map[string]*configs.Variable) (ter
 	return variables, nil
 }
 
+// ParseExpression is a wrapper for a function that parses JSON and HCL expressions
+func ParseExpression(src []byte, filename string, start hcl.Pos) (hcl.Expression, hcl.Diagnostics) {
+	if strings.HasSuffix(filename, ".tf") {
+		return hclsyntax.ParseExpression(src, filename, start)
+	}
+
+	if strings.HasSuffix(filename, ".tf.json") {
+		return nil, hcl.Diagnostics{
+			&hcl.Diagnostic{
+				Severity: hcl.DiagError,
+				Summary:  "JSON configuration syntax is not supported",
+				Subject:  &hcl.Range{Filename: filename, Start: start, End: start},
+			},
+		}
+	}
+
+	panic(fmt.Sprintf("Unexpected file: %s", filename))
+}
+
 func getTFDataDir() string {
 	dir := os.Getenv("TF_DATA_DIR")
 	if dir != "" {

tools/go.mod

@@ -6,7 +6,7 @@ require (
 	github.com/hashicorp/hcl/v2 v2.5.1
 	github.com/hashicorp/terraform-plugin-sdk v1.13.1
 	github.com/serenize/snaker v0.0.0-20171204205717-a683aaf2d516
-	github.com/terraform-linters/tflint-plugin-sdk v0.1.1
+	github.com/terraform-linters/tflint-plugin-sdk v0.1.2-0.20200613135440-8f8f107dab08
 	github.com/terraform-providers/terraform-provider-aws v2.65.0+incompatible
 )